Okay, I figured this might be interesting for some people. Note that I'm just making a list of the new characters you can use. I don't have a complete list, but I'm making it based on gameplay footage I've seen in trailers and other sources. If I'm missing one, let me know so I can put it up.

Ovan you can't get. Unless you have Action Replay or Codebreaker. I've seen some people use him (and a number of other nice characters). But you need that hacking stuff. I don't know where to find it and don't feel like buying one either.